CVE-2026-87802 — CRITICAL (9.1)

Vulnerability Description

Improper verification of cryptographic signature vulnerability in Apache Syncope. When SRA is configured for OAuth 2.0 without JWKS set URI assigned, an attacker can forge arbitrary JWTs to impersonate any user identity and permissions, gaining full access to services proxied by SRA. This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 through 4.0.7, from 4.1.0-M0 through 4.1.2. Users are recommended to upgrade to version 4.0.8 / 4.1.3, which fix this issue.

CVSS Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

HIGH

Integrity

HIGH

Availability

NONE

Related Weaknesses (CWE)

CWE-347

References

FAQ

What is CVE-2026-87802?

CVE-2026-87802 is a vulnerability with a CVSS score of 9.1 (CRITICAL). Improper verification of cryptographic signature vulnerability in Apache Syncope. When SRA is configured for OAuth 2.0 without JWKS set URI assigned, an attacker can forge arbitrary JWTs to imperso...

How severe is CVE-2026-87802?

CVE-2026-87802 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2026-87802?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.